DE10341594A1 discloses a method for directly measuring the geometric errors of the numerical control machine tool, the machining center or the coordinate measuring machine. The beam from the laser interferometer is splitted to be parallel to the three linear motion axes of the equipment listed above. The laser interferometer directly measures the geometric errors of the three linear motion axes. However, the system configuration is complicated, and the assembly and adjustment of the system is difficult. Moreover, the roll error of the three linear motion axes cannot be measured.
In prior art, there exist no such a measurement system which offers simple configuration and convenient operation, and can directly measure up to 21 GMEs of three mutual perpendicular linear motion axes by a single installation and step-by-step measurement.